第01章软件工程学概述.ppt

Agile means being able to quickly change direction. It is based on rapid prototype and incremental models. Agile methods emphasize working software as the primary measure of progress. Combined with the preference for face-to-face communication, agile methods usually produce less written documentation than other methods. In an agile project, documentation, Gantt charts and other project artifacts all rank equally with working product. However, when stakeholders are asked to prioritise deliverables for demonstration at the end of the current iteration, they generally prefer to see working product. Stakeholders are encouraged to prioritise iteration outcomes based exclusively on business value perceived at the beginning of the iteration. If documentation represents higher business value than working software in any particular iteration then stakeholders give it a higher priority than working software. The (cross-functional) development team will accordingly produce that documentation instead of lower priority software.[citation needed] * Goal of XP (imp) Extreme Programming Explained describes Extreme Programming as being: An attempt to reconcile humanity and productivity A mechanism for social change A path to improvement A style of development A software development discipline The main aim of XP is to reduce the cost of change, by introducing basic values, principles and practices. By applying XP, a system development project should be more flexible with respect to changes. * MS is not well known for its software development, neither in quality nor in delay respect in SE. They are good for marketing. * 软件可嵌入到各种系统中，比如交通运输、医疗、办公、娱乐等，直接影响着人们的生活。作为一门研究如何规范化的开发软件的学科，软件工程的观点-----计算机软件是最终产品 20世纪60年代中期以前，通用硬件相当普遍，软件却是为每个具体应用专门编写的。往往除程序清单外没什么文档资料保存 从20世纪60年代中期到70年代中期，出现了软件作坊，但还是沿用早期个体化的软件开发方法。随着计算机应用的日益普及，软件数量急剧膨胀 在全球软件领域，1960年代出现软件危机，软件工程被正式提出，开始注重软件结构的研究;到了1970年代，程序设计方法学成为研究热点，出现了结构化分析和设计方法;1980年代，软件开发方法学成为研究重点，面象对象技术开始出现并逐步流行;到了1990年代，软件复用和软件构件技术被视为解决软件危机的一条现实可行途径，基于构件